This piece of advice may sound like a hokey song refrain or a plug from a
resort advertisement. But a new study suggests that there may be something to
The study found that postsurgery patients experienced less psychological
stress and pain, and used less pain medication, when housed on the sunny side
of the hospital.
The investigation was headed by Jeffrey Walch, an M.D.-Ph.D. candidate and
medical researcher at the University of Pittsburgh. Walch was an architect
major in college and is interested in how architectural design and
environmental factors might affect patient recovery in the hospital.
It is well documented that light can counter seasonal affective disorder,
but other studies have suggested that light can positively affect hospital
patients. For example, light exposure has been linked to a reduced hospital
stay for heart-attack patients.
Still other findings have indicated that light can increase the
concentration of the neurotransmitter serotonin and that serotonin in turn can
inhibit pain pathways in the central nervous system.
So Walch and colleagues at the University of Pittsburgh and Carnegie Mellon
University decided to see whether sunlight might favorably impact hospital
patients' stress perception, pain perception, and pain-medication use.
They enrolled 89 subjects who were about to undergo spinal surgery.
Forty-four had been housed on the sunny side of the hospital and 45 on the
shady side of the hospital simply on the basis of room availability. However,
Walch and his team made sure that subjects housed on the sunny side did not
differ significantly from the other subjects on demographics, clinical
diagnosis, surgical procedure, use of pain medication before hospitalization,
use of pain medication in the operating room, and use of pain medication in
the postanesthesia care unit.
Once subjects were moved from the postanesthesia care unit to a hospital
room, and until their discharge from the hospital, the researchers measured
daily sunlight intensity in their hospital rooms.
They measured daily sunlight intensity in a subject's room as follows:
Five times in the morning and five times in the afternoon, they measured
direct sunlight in the room (the intensity of sunlight at the point where it
entered the room); reflective sunlight (the intensity of sunlight reflected
off the patient); and ambient sunlight (the intensity of sunlight reflected
off interior surfaces). Direct, reflective, and ambient sunlight intensity
results for the morning were then averaged. The same was done for direct,
reflective, and ambient sunlight intensity results for the afternoon. Results
for the morning were then multiplied by the number of morning hours, and
results for the afternoon were multiplied by the number of afternoon hours.
The total sunlight intensity results for the morning and the afternoon were
then added, giving the cumulative sunlight intensity for the day.
Using these yardsticks, the investigators found that subjects on the sunny
side of the hospital were exposed to 46 percent greater-intensity sunlight on
average than were subjects on the shady side.
Upon discharge from the postanesthesia care unit and from the hospital,
subjects filled out four questionnaires—the Profile of Mood States
anxiety scale, Center for Epidemiological Studies Depression Scale, Perceived
Stress Scale, and McGill Pain Questionnaire.
These instruments allowed the researchers to determine how subjects'
anxiety, depression, perceived stress, and perceived pain on discharge from
the postanesthesia care unit compared with those factors on discharge from the
hospital, and also how the sunny and shady groups compared.
Subjects on both the sunny and shady sides experienced comparable levels of
anxiety, depression, stress, and pain upon discharge from the postanesthesia
care unit. They also experienced comparable levels of anxiety and depression
upon hospital discharge, and these levels were similar to what they had
experienced upon discharge from the postanesthesia care unit.
However, stress levels at hospital discharge were found to be significantly
lower in the sunny-room group than in the shady-room group. And the sunny-room
group's stress levels were lower at hospital discharge than at the time of
discharge from the postanesthesia care unit, but this was not the case for the
With regard to pain, both groups reported less upon hospital discharge than
after discharge from the postanesthesia care unit, but the sunny-room group
reported considerably less pain than the shady-room group.
Subjects were also evaluated for the amount of pain medication they had
used during hospitalization.
The sunny-room group was found to have used 22 percent less pain medication
than the other group had.
"I was happy with the results," Walch told Psychiatric
News. "I think that the subject will be investigated further and
that it may impact the hospital design of the future. But I was surprised that
we didn't just show a decrease in stress, but also a decrease in pain
perception and a decrease in pain-medication usage."
Still another surprise, Walch said, was that while the sunny-room group
experienced significantly less stress at hospital discharge, it was not
statistically linked with the sunny-room group's lower levels of analgesic
use. So he does not believe that subjects' decreased pain medication use
resulted from having less psychological stress. "They are separate
outcomes," he said.
The study was funded by the University of Pittsburgh Medical Center Healthy
Lifestyle Program and a grant from Carnegie Mellon University's Undergraduate
Research Initiative. Results were published in the January-February
An abstract of the report, "The Effect of Sunlight on
Postoperative Analgesic Medication Use: A Prospective Study of Patients
Undergoing Spinal Surgery," is posted online at<www.psychosomaticmedicine.org/cgi/content/abstract/67/1/156>.▪